Record Details
Estrogen regulation of pituitary function in the gonadectomized sheep
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Estrogen regulation of pituitary function in the gonadectomized sheep |
| Names |
Cooper, Gordon Jay
(creator) Ellington, Earl F. (advisor) |
| Date Issued | 1966-09-02 (iso8601) |
| Note | Graduation date: 1967 |
| Abstract | A total of five individual experiments were conducted with gonadectomized, male sheep to study the influence of estrogen on the plasma level of pituitary activities, with the greatest emphasis given to gonadotropic activity. Estrogen treatments employed were as follows: 1. 12 mg. diethylstilbestrol (DES) implanted subcutaneously. 2. 1 mg. DES injected intramuscularly daily for 4 consecutive days. 3. 1 mg. estradiol benzoate (EB) injected intramuscularly daily for 4 consecutive days. 4. 1 mg. EB injected intramuscularly daily for 10 consecutive days. 5. 0.025 mg. EB injected intramuscularly daily for 10 consecutive days. To determine sequential changes in plasma activities, samples of cavernous sinus blood were collected at intervals prior to, during and following estrogen treatments and bioassayed as raw plasma or fractions of plasma obtained by pH and acetone precipitations. Hypo-physectomized, immature, female rats were utilized as the assay animals. A significant depression in plasma gonadotropic activity to all estrogen treatments was clearly demonstrated as evaluated by the ovarian and uterine weight responses in the assay animals. Histological examination of the rat ovarian follicles and interstitial tissue revealed that the estrogen inhibition of plasma gonadotropic activity involved both FSH and ICSH components. The gonadotropic depression was apparent for periods of time following estrogen withdrawal, as well as being evident during treatment. Tail length, epiphyseal width, adrenal weight, thymus weight and thyroid weight responses of the assay animals to the injected plasma did not establish marked trends as did the gonadal responses. These findings are discussed in relationship to current concepts of estrogen-pituitary interrelationships. |
| Genre | Thesis/Dissertation |
| Topic | Estrogen -- Physiological effect |
| Identifier | http://hdl.handle.net/1957/47771 |
